Problem: Simplify the following expression: ${10r-12-3r-3}$
Rewrite the expression to group the ${r}$ terms and numeric terms: $ {10r - 3r} {-12 - 3}$ Combine the ${r}$ terms: $ {7r} {-12 - 3}$ Combine the numeric terms: $ {7r} {-15}$ The simplified expression is $7r-15$